The invention resides in an air spring strut for wheel suspensions of motor vehicles including an air spring head supported on the vehicle body and an outer guide structure for an air bellows, whose inner guide structure is formed by an air spring piston which surrounds a shock absorber having a piston mounted in the air spring head and a dampening cylinder connected to the wheel suspension and which sealingly engages the damping cylinder.
Such air spring struts are known, for example, from DE 197 53 637 A1. As vehicle spring struts, they are well known under the name McPherson struts, which are in wide use as wheel guide and support elements. They are connected at their lower ends to transverse wheel links and are attached at their top end to the vehicle body. However, in such an arrangement, the wheel support forces generate transverse forces on the shock absorber included in the strut, which adversely affects the spring characteristics. The object of DE 197 23 637 A1 is to generate forces and which counteract those transverse forces and which reduce the friction in the shock absorber, which friction detrimentally affects the response behavior of the strut. To achieve this, the air spring bellows in connection with a rigid connection of the air spring piston or the damper tube of the shock absorber is so designed that appropriate transverse forces are generated in a pressure-dependent manner.
It is the object of the present invention to provide an air spring strut with a shock absorber, which is essentially not subjected to transverse forces so that the response behavior of the spring strut is improved. Also, the strut should be relatively slim and spring and steering movements which move the strut out of its design position should not negatively affect the response characteristics of the spring and especially of the shock absorber inspite of transverse forces effective on the strut.